The rlcompleter module does not work if __main__ cannot be imported, even though it can be used without it. For example, on the App Engine, __main__ is not usable.
If one creates the example app described at https://developers.google.com/appengine/docs/python/gettingstartedpython27/helloworld, and adds "import rlcompleter" to the top of helloworld.py, you get the following error in the AppEngine
Traceback (most recent call last):
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/runtime/wsgi.py", line 196, in Handle
handler = _config_handle.add_wsgi_middleware(self._LoadHandler())
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/runtime/wsgi.py", line 255, in _LoadHandler
handler = __import__(path[0])
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 692, in Decorate
return func(self, *args, **kwargs)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1766, in load_module
return self.FindAndLoadModule(submodule, fullname, search_path)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 692, in Decorate
return func(self, *args, **kwargs)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1630, in FindAndLoadModule
description)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 692, in Decorate
return func(self, *args, **kwargs)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1577, in LoadModuleRestricted
description)
File "/Users/aaronmeurer/Desktop/helloworld/helloworld.py", line 2, in <module>
import rlcompleter
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 692, in Decorate
return func(self, *args, **kwargs)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1766, in load_module
return self.FindAndLoadModule(submodule, fullname, search_path)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 692, in Decorate
return func(self, *args, **kwargs)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1630, in FindAndLoadModule
description)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 692, in Decorate
return func(self, *args, **kwargs)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1577, in LoadModuleRestricted
description)
File "/sw/lib/python2.7/rlcompleter.py", line 43, in <module>
import __main__
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 692, in Decorate
return func(self, *args, **kwargs)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1766, in load_module
return self.FindAndLoadModule(submodule, fullname, search_path)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 692, in Decorate
return func(self, *args, **kwargs)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1630, in FindAndLoadModule
description)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 692, in Decorate
return func(self, *args, **kwargs)
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1577, in LoadModuleRestricted
description)
ImportError: Cannot re-init internal module __main__
Now, I don't really understand what the issue is here. I don't really get how __main__ is supposed to work, whether this is something that might be expected to happen in an environment that isn't highly modded like the App Engine's. Probably this should at least be considered an App Engine bug.
My point is that it's possible to use the rlcompleter module completely without __main__, if one passes the optional argument to Completer.
My suggestion is to catch ImportError when importing __main__, and if it isn't importable, make the argument to Completer required. It should be a minimal code change. |